Elementos majoritários, minoritários e traço em vinhos provenientes de países produtores na América do Sul (Argentina, Brasil, Chile e Uruguai) foram determinados. A espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES) e a espectrometria de massa com plasma indutivamente acoplado (ICP-MS) em conjunto com nebulização pneumática e/ou nebulização ultra-sônica foram utilizadas. Foram determinados 45 elementos (Al, Ag, As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Gd, Ho, K, La, Li, Lu, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Pr, Rb, Sb, Sn, Se, Sm, Sr, Tb, Ti, Tl, Tm, U, V, Yb e Zn) em 53 vinhos tintos. Mediante análise multivariada, os vinhos puderam ser discriminados de acordo com o país de origem, independentemente do tipo da uva. Os elementos discriminantes foram Tl, U, Li, Rb e Mg.Major, minor and trace elements in wines from wine-producing countries in South America (Argentina, Brazil, Chile, and Uruguay) were determined. Inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) combined with pneumatic and/or ultrasonic nebulization were used. The concentrations of 45 elements (Al, Ag, As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Gd, Ho, K, La, Li, Lu, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Pr, Rb, Sb, Sn, Se, Sm, Sr, Tb, Ti, Tl, Tm, U, V, Yb, and Zn) in 53 red wines were determined. By means of multivariate analysis, the wines could be discriminated according to the country of origin, regardless of the type of grape. The discriminant elements were Tl, U, Li, Rb, and Mg. Keywords: red wine provenance, multivariate analysis, element concentration, ICP OES, ICP-MS IntroductionWine has a long history dating back to biblical times. With the evolution of the viticulture, a wide sort of wines became available to consumers due to the varieties of grape grown and different methods of wine producing.Several elements (especially Cd, Cu, Fe, Mn, Sn and Zn) when present in excessively high concentration in wines, adversely affect the organoleptic quality and the stability of the wine. They may cause a metallic taste, undesired color change or give rise to obstinate hazing and cloudiness. 1 The concentration of some elements can be a sort of fingerprint of the wine. The element profile does not depend exclusively on the geochemistry of the provenance soil but is affected by the winemaking process and the grape variety. Identifying the origin of wine is of great interest to producers and consumers, as it provides criteria for deciding about the quality of wine. Therefore, a method for verifying authenticity is an essential requirement to control the product origin claims.Studies have shown that the concentration profile of elements can be used to identify the provenance of a wine as well as its authenticity.2-6 Lanthanides have been suggested as a fingerprint for the provenance of wines.2,4 However, caution must be taken because contamination may occur at the production step, transport and storage, as well as by inadequate winemak...

Baixas concentrações dos catorze elementos de ocorrência natural da série lantanídeos foram diretamente determinadas por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Avaliaram-se interferências espectrais e linhas espectrais mais adequadas foram selecionadas. Os desempenhos da nebulização pneumática e ultra-sônica foram comparados com respeito aos limites de detecção, para ambas as posições de observação do plasma, radial e axial. A influência da potência de radiofrequência sobre a precisão e exatidão foi também investigada para os dois tipos de nebulizadores. O método foi aplicado à determinação dos lantanídeos em amostras ambientais (sedimentos, cinza de carvão e água fluvial). Este trabalho demonstrou que é possível a determinação direta de baixas concentrações (i.e. ng g -1 e ng L -1 ) dos lantanídeos de ocorrência natural por ICP OES.Low concentrations of the fourteen naturally occurring lanthanides were directly determined by inductively coupled plasma optical emission spectrometry (ICP OES). Spectral interferences were evaluated and the most appropriate spectral lines selected. Pneumatic and ultrasonic nebulization performances were compared with respect to limits of detection for both radial and axial viewed plasma. The influence of plasma applied power on precision and accuracy was studied for both nebulizers. The developed method was applied to lanthanides determination in environmental samples (sediments, coal fly ash and river water). This work demonstrates that the use of ultrasonic nebulization combined with axially viewed plasma allowed direct determination of low concentrations (at ng g -1 and ng L -1 levels) of all naturally occurring lanthanides by ICP OES. Keywords: lanthanides, ICP OES, ultrasonic nebulization, pneumatic nebulization, environmental samples IntroductionThe elements of the lanthanides series, ranging from lanthanum to lutetium comprises fithteen homologous trivalent metals, of which fourteen commonly occur in nature. Promethium does not occur naturally. Lanthanides mobilization from their natural sources has increased in the last decades. Because of their diversified physical and chemical properties, the lanthanides elements have been widely used in a number of fields (e.g., in microelectronics and optics, in material science or in nuclear reactors, in biomolecular research or in medical diagnostics).1-3 The lanthanides are also often used in fertilizers 4 or as feeding markers in nutritional and agronomic studies. [4][5][6] These elements have also been used as fingerprint markers for cement and concrete 7 and in geological 8 or palenteology studies. 9Uses and applications of lanthanides are still increasing and so are the associated emissions to the environment. In recent years, lanthanides-rich fertilizers have being widely used in China to enhance yield and improve crop quality. It is reported that application of these fertilizers not only increases the yield but also brings many visual benefits to plants including darker green foliage, enha...

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A cloud point extraction (CPE) method is proposed for pre-concentration of lanthanides and subsequent determination using inductively coupled plasma optical emission spectrometry (ICP OES). Octylphenoxypolyethoxyethanol (Triton X-114) and 1-(2-thenoyl)-3,3,3-trifluoraceton (TTA) are used as surfactant and complexant of the lanthanides, respectively. A three-factor Doehlert matrix design with seven, five, and three levels is used to optimize the TTA and Triton X-114 concentration and the pH of the solution, respectively. The better conditions for pre-concentration are 0.001 to 0.005 mol L À1 TTA, 0.05 to 0.3% (m/v) Triton X-114 and pH from 5.5 to 7.0. Under these conditions, the fourteen naturally occurring lanthanide elements can be pre-concentrated together and then measured. The conditions established were pH 6.0 and 0.175 (m/v) Triton X-114 for all investigated elements; 0.005 mol L À1 TTA for Sm, Eu, Gd, Tb, Ho, Yb and Lu; and 0.001 mol L À1 TTA for La, Ce, Pr, Nd, Dy, Er and Tm. By using axially viewed plasma and pneumatic nebulization/aerosol desolvation, the limits of detection were 0. 028, 0.099, 0.103, 0.020, 0.018, 0.014, 0.013, 0.047, 0.015, 0.009, 0.022, 0.003, 0.002 and 0.002 mg L À1 for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, respectively. The proposed method was applied for lanthanides determination in mineral water, river water and reference water.

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Estudo comparativo dE métodos dE prEparo dE amostras dE tinta para a dEtErminação dE mEtais E mEtalóidEs por técnicas dE (3) decomposition in open vessel using HNO 3 + HF and ashing. Paints of different types and colours were analyzed, in which several elements were determined using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP OES). It was observed that method (1) is appropriate for trace, minor and major elements determination, while method (3) is appropriate for Ti.

This work deals with As determination in marine sediment using ultrasound for sample preparation. It is shown that As can be quantitatively extracted from marine sediment using 20% (v/v) HCl and sonication. The slurry is centrifuged and the analyte is determined in the supernatant by hydride generation atomic absorption spectrometry (HG AAS). A flow injection (FI) system is employed for hydride generation, with 0.5% (m/v) NaBH4 used as reducdant and a 20% (v/v) HCl used as sample carrier. The limit of quantification is 1.6 μg g -1 of As, which is based on 800 μl of sample solution and 0.200 g of sample mass in a volume of 50 mL. Certified and non certified marine sediment samples were analyzed; the results were in accordance with the certified or reference values. Speciation analysis by HPLC-ICP-MS showed that As(V) is the only detectable As species present in the supernatant of the centrifuged sample.